Door-operating means



Feb. 19, 1929. 1,702,577 H. ROWNTREE DOOR OPERATING MEANS Filed Nov. 22,1924 2 Sheets-Sheet 2 l I'M INVENTOR Feb. 19, 1929. 1,702,577

H. ROWNTREE DOOR OPERATING MEANS Filed Nov. 22, 1924 2 Sheets-Sheet l J/ATI'ORNE Patented Feb. 19, 1929.

UNITED STATES PATENT OFFICE.

HAROLD ROWN'IREE, OF SCARS DALE, NEW YORK, ASSIGNOR TO NATIONAL IPNEU-MATIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF WEST VIRGINIA.

DOOR-OPERATING MEANS.

Application filed November 22, 1924. Serial No. 751,497.

This invention relates to the operation of doors, and, while adapted forgeneral application, is particularly intended for use in connection withthe doors of cars and buses, in which environment, it may also serve tooperate and controlthe hinged or folding steps with which cars and busesare frequently provided.

The primary object of the invention is to provide a very simple andcompact mechanism for the control and operation of doors, either aloneor in conjunction with folding or hinged steps.

hen utilized to operate and control a hinged cardoor and step, theinvention may conveniently embody a prime mover in the form of areversible electrical motor connected with the doorand step by gearingcon nections including a friction clutch through which power istransmitted from the motor to the door and step. sociated an electriccircuit by which the operations of the motor may be controlled to openand close the door and correspondingly move the step. This controlcircuit includes switch mechanism for reversing the feed of current tothe motor and this switch mechanism may be either manually orautomatically operated or may be controlled conjointly by an auto--matic and manual operation. Moreover, I may include in the controlcircuit means which renders the operation of such circuit dependent uponthe stopping of the car. In other words, such means may be soconstituted that the operation of the doors cannot take place unless thecar is at rest, the purpose of which arrangement is to obviate accidentswhich are apt to result if persons are permitted to board or leave thecar while it is in motion.

Inasmuch as the door is opened and closed through friction driveconnections, means is preferably provided for looking a door in itsclosed position independently of such connections, so that if personslean or are thrown against the door, the door will not inadvertentlyopen. This means may partake of various forms which, however, inpractice, preferably include automatic mechanism for releasing the doorwhen it is desired to open the same through the connections describedalthough emergency manually operable devices also preferably included topermit the door to be released through a manual opa re,

With the motor is as-- oration if such should be desired for any reason.7 7

An import-ant feature of the invention resides in the pronouncedsimplicity of the structural elements entering into its practicalembodiments, and the unfailing manner of its operation.

' The structure may be'made very compact and such wiring, as isassociated therewith and forms part thereof, is relatively simple andlends itself to very eflicie-n't control either through purely manual orautomatic means or a combination of bot-h.

A further important feature of the invention is found in the simpledriving connectionsbetween the motor and the door. I In practice, thesedriving connections preferably consist in aworm fixed on the armatureshaft of the reversible motor and driving a worm wheel with which afriction disk is rigid. With this friction, disk cooperates another diskrigid with the pinion which meshes with a gear segment fixed on the doorshaft. A spring serves to force these disks together under elasticpressure and thus renders the door shaft responsive to the operations ofthemotor.. At the same time, the cooperating friction disks form betweenthese parts a yielda-ble connection which will permit overtravel of themotor after the door is opened or closed without overloading the motor,which might result in burning out the motor or blowing a fuse.

Features of the invention, other than those specified, will be apparentfrom the hereinafter detailed description and claims, when read inconjunction with the accompanying a suitable casing, the cover of whichis removed in the showing of Figure 1, so that said figure, in effect,corresponds to a section taken on the line 11 ofFigure 2.

Figure 2 is a section on the line 2-2 of Figure 1 showing certain partsin elevation in the interest of clearness.

Figure 3 is a vertical section taken through the upper portion of a doorand through the juxtaposed portion of the door casing and illustratingin section means embodying the present invention for normally lockingthe door in closed position; and,

Figures 4 and 5 are wiring diagrams showing different ways in which theoperation of the mechanism, illustrated in Figures 1 and 2, may becontrolled.

In car construction, the folding or hinged doors with which such carsare usually provided are generally mounted on one or more verticalshafts which forms the pivot or pivots of the door or doors, While thestep is mounted to pivot on a horizontal axis and is generally connectedto the shaft which operates the door in such manner that when the shaftis rotated through an angle of 90 de grees, the door is opened or closedand the step is simultaneously extended or withdrawn. This constructionis so well known that it has not been considered necessary to show it inthe drawings, so that I have simply a illustrated in Figures 1 and oneend of the door operating shaft which bears reference character 1.

In accordance with the present invention, 1 aflix to the shaft 1 a gearelement 2, and inasmuch as it is the general practice to place the shaft1 relatively close to a post or some other fixed part of the carstructure, I prefer, in the interest of compactness, to make the gearelement 2 in the form of a segment, as shown best in Figure 1. Thissegment is firmly affixed to the shaft and when operated will serve toimpart rotation thereto.

3 designates a prime mover by means of which operation of the door iseffected and in practice this prime mover is preferably in the form of asmall reversible motor of which I preferably employ one of the compoundWound type, which will be able to make a rapid start and at the sametime will not exceed its rated maximum speed. This motor is mountedwithin a suitable casing 4, prefer-- ably made sufliciently large toalso enclose the end of the shaft 1 and the gear segment 2 associatedtherewith.

On the armature shaft 5 of the motor, a worm 6 is aihxed and this wormmeshes with a worm wheel 7 mounted to freely rotate on a stub shaft 8carried by the casing 4, as shown best in Figure 2.

A friction disk 9 is rigid with the worm wheel 7 and is adapted forcooperation with another friction disk 10 rigid with the pinion 11. Thepinion 11 and disk 10 are also mounted to freely rotate 'on the shaft 8and said shaft is so positioned. relative to the shaft 1, that thepinion 11 will mesh with the gear segment 2 on the latter shaft. Aspring 12 bears against the worm wheel 7 and forces the dislr 9 underelastic pressure against the disk 10 to establish a friction driveconnection between these parts. In this manner, the shaft 1 is maderesponsive to the operations of the prime mover 3, though it will beunder stood that the presence of the friction disks will permitovertravel of the motor after the door has been fully opened or closedand will also insure against injury to persons who may be caught by thedoor. The motor is thus safeguarded against burning out due to overloadsand the inconvenient blowing of fuses is moreover obviated.

In Figures 1 and 2, the arrangement has been shown as adapted to operateone door, either of the single hinged type or of the folding type,embodying a plurality of panels, but it will be understood that inpractice this arrangement may be duplicated for a plurality of doors orthe shaft 1 of one door may be geared or otherwise connected to the likeshaft of a corresponding double door, or other modifications, which willsuggest themselves to those skilled in the art, may be employed. Otherarrangements adaptable for use in this connection will be hereinafterreferred to. However, in every case, the invention will remainsubstantially the same.

The control of the motor 3 may be accomplished in different ways, butvery practical means is illustrated diagrammatically in Figures 4 and 5.

In the former of these figures, 13 designates the handle of manuallyoperable switch mechanism, and 6 the motor to be controlled thereby. Inthe event that several doors are to be controlled from a common point, anumber of these motors may be made controllable from the switch handle13, by merely wiring them in parallel with one another as would be thecase if two or three doors of the same car were to be controlled by oneconductor or one motorman.

The handle 13 forms part of switch mechanism including two movablecontacts 14 and 15, which are rigid with the handle 13, though insulatedtherefrom and both of which including thehandle are movable aboutthecommon pivot 16. The contact arm 14 is adapted to be engaged at alltimes by a brush 1?, while the contact arm 15 is engaged by a similarbrush 18. Additional fixed contacts 19, 20, 21, 22, 23 and 24 areprovided and are adapted to be engaged by the contacts 14 or 15 when thehandle 13 is operated in one direction or the other.

It will be apparent that, when the handle 13 is in zero or neutralposition shown in Figure 4, none of the last mentioned fixed contactswill be engaged by either of the contact strips 14 and 15. If, however,the handle 13 is moved from its central position to the left, the stri p14 will engage with both the contacts 19 and 20, while the strip 15 willengage with the contact 24.

The motor 6 is shown in Figure 4 as a compound wound motor and is sowired with re spect to the contacts which I havedescribed that thefollowing circuits will be completed when the handle 13 is moved to theleft as stated; from a source of current supply 25, cu-rrent'will flowthrough a wire 26 to the brush 17 and through the strip 14 to thecontact 20 and thence through'a wire 26 to the lower armaturebrush 27 ofthe motor. Leaving the armature through the upper brush 28, the currentflows through awire 29 to contact 24, through strip 15 to brush 18 andfrom brush 18 through wire 30 to the series field31 of the motor.Leaving the series field, the current passes through the Wire 32 toground at 33. This will cause the motor to operate in one direction, e.g., the direction appropriate to bring about the opening of the door.If, in contradistinction, to the operation previously described, thehandle 13 is moved to the right, the following circuits will becompleted; from source 25 through Wire 26 to brush 17, strip 14, contact22, cross connection 34, to contact 24, through wire 29 to upperarmature brush 28. Through the armature to lower armature brush 27 andby wire 26 to contact 17. Thence through cross connection 35 to contact23, strip 15, brush 18, and Wire 30 to the series field, after which itpasses through the return 32 to ground at .33, with the result that themotor is operated in the opposite direction.

WVhen the arm 13 is moved in either direction, as has been described,the motor will operate so long as it is held in either of its terminalpositions and said motor will be tie-energized or will cease to operatewhen the handle 13 is returned to'neutral position.

It may frequently be desirable in adapting the present invention to theoperation and control of car doors, to render the operation oft-he doorsprovisional on the stopping of the car, and while this may beaccomplished in various ways, one typical form of means which may beemployed for this purpose is illustrated in Figure 4 as comprisingswitch mechanism generally designated by the refer-.

ence character 36. This switch comprises a bridge piece 37 which, asshown, is pneu lmatically controlled. It is illustrated as secured to apiston 38 operable withina cylinder 39. A spring 40 normally forces thebridge piece free from contacts'41 and 42 which are included in the wire26 and thus normally breaks any circuit which might be otherwise madethrough this wire.

Apipe 43 is connected to the air-brake system of the car, so thatwhenthe air is on to actuate the brakes, pressure is admitted to thecylinder 39 and moves the piston 38 to cause the bridge piece 37 tobridge the contacts 41 and 42.

WVhen this arrangement is employed, it will be apparent that theoperation of the doors is dependent upon the stopping of the car.

Manifestly, there are many ways in which power might be applied tocontrol the operations of the bridge piece 37 and while I have shown itas pneumatically operated, it

might be electrically operated, .or otherwise.

The purpose of the switch 36 is to make this circuit inoperativewhenever the car controller, or the brakes, or some other essential partof the car operating system, has

been so manipulated that it would be no longer desirable for the doorsto be operative. In the principal form shown in the drawings, apneumatic operation is illustrated, but in lieu of the cylinder andpiston, I might well employ a magnet or solenoid in which event thecontacts 41 very probably should be placed onthe other side of thebridge piece member. In lieu of the structure shown, however, themanually operated switch for controlling the doors can have its feedcircuit coming through either a contact on the car controller or througha contact operated by the pressure either from the brake pipe system orfrom the brake controller, so that no doors can be opened when the caris running. Manifestly if desired the starting of the car can also bemade to cause any open door to close by a pressure cylinder connected tothe brake system, orby a magnet connected to the controller systempositively moving the door controlling switch to closing position whenthe car is started.

In Figure 5, the same general arrange- I the weight is imposed on theplatform, thebell cranks are tilted and act through the link 44 to movethe handle 13 to its other extreme position. When this constructionis-employed a manually operable switch 50 is preferably employed in lieuof the switch 36 of Figure 4..

The switch 50 is placed in a position to be readily accessible tothe carattendant and its purpose is to stop the motor from further operationafter the door or doors are closed and there are no more passengers toalight and to also make the treadle device inoperative whenever it isdesired that it should not be used.

If desired, a switch similar to the switch 36 may be arranged in serieswith the switch 50 so as to render the motor irresponsive to theoperations of either the switch 50 or the treadle operated switch unlessthe car'is at.

rest.

Inasmuch as the connection between the That is toy door operating motorand the door shaft is through a friction device, it might be possiblefor someone leaning against the door to cause it to open, and toovercome this possibility, I preferably employ a locking device inconjunction with the door and which device is preferably in the form ofa latch or detent adapted to latch over the upper edge of the door 51and so normally retain it in closed position. Different means may beemployed to operate this latch and the latch may be of different forms,but Figure 3 of the drawings shows an illustrative construction.

In Figure 3, the latch is in the form of a bell crank 52, one arm 53 ofwhich is adapted toengage withthe upper portion of the door 51, whilethe other arm 54 of which projects upwardly and has secured thereto aspring 55 which serves to normally impelthe arm 53 into engagement withthe door. The latch may be moved in the opposite direction in manydifferent ways, but for the purpose of illustration, the means shown foraccomplishing this result is in the form of a piston 56 to which fluidpressure, as from the air brake system, is applied when the car isstopped, with the result that when the car stops the latch is moved awayfrom the door. so that the door can be opened. In lieu of thepneumatically operated piston 56, I may, however, employ electromagneticmeans and the power may be transmitted to the latch either to directlyraise the latch or the latch can be raised by a spring which is heldagainst action by the power means. In one case, the door will be latchedshut, whenever, and as long as, the power means are applied, and in theother case, the door will be latched shut whenever the power means arenot applied. to which of these two methods is used in practice of coursedepends upon how the operating power is controlled.

If electrical means are employed to actuate the latch, it can be cut onor off simultaneously with the motion of the manually operated. switchthat controls the door, or with and by the action of an extra segment onthe car controller, or with and by the action of the pneumatic switch inconjunction with the air brake or air brake valve. All of these methodsare equally applicable for use with this type and in all cases they workto cause the door to be locked shut by a detent whenever, under normalconditions, the door should not be used.

It is important, however, that some means should be provided to permitthe unlocking of the latch in the case of emergency or otherwise and inevery instance, irrespective of the automatic control of the latch suchmanual means is embodied.

In the construction shown in Figure 3 of the drawings, the manual meansconsists of a rod 57 connected to the arm 54 of the latch and extendinginto a convenient position to permit it to be operated manually torelease In the accompanying. drawings, I have shown a connection betweenthe driving motor 3 and the door shaft of one door, but, in

Jractice man modifications or am lilica;

tions of this simple electric power engine can be made. For example, ifthe ordinary four panel folding door is used, and which includes twovertical shafts, one for each door,- there can be a mere duplication ofthe mechanism shown in Figures 1 and 2, for eachof these shafts and themotors can be arranged in parallel in the wiring diagrams of eitherFigures 4 and 5, so that both motors are con trolled simultaneously.Moreover, instead of duplicating the motor arrangement, one meter may beused and the two door shafts connected by across connection as iscustomary in the pneumatic operation of doors. Moreover, if separateelectric engines, as shown in Figures 1 and 2, are employed for theentrance and exit doors, the entrance door can be controlled by amanually operated switch, as described and shown in Figure l, and theexit door can be controlled by a treadle device inside the doorwaywhich, when depressed, completes the circuit of the motor for openingthat door, and, when liberated, completes the circuit for closing thatdoor.

In the latter case, the feed connection of the treadle switch whichwould have to be broken before the motor operated there-by would ceaserunning, can be controlled either by the switch of the entrance door orby an additional contact on the car controller or by a switch operatedby pneumatic pressure from the air pipe valve or from the air brakecontroller as will be apparent from the foregoing desciption, so thatwhen the motorman had either started the car or was prepared to startthe car, the exit door could no longer be opened.

I have described the step asmechanically connected in any suitable andwell known manner to the shaft on which the associated door is mounted,but, in practice, an independent motor, constructed as shown in Figures1 and 2, might be employed to operate the step independently withoutdeparting from this invention.

While I have shown and described various structures and arrangementsembodying the principle of my invention, I wish it to be understood thatmy broad invent-ion, as defined in the claims, is not limited orrestricted to any specific arrangement or to any detail thereof, as itisobvious that many modifica tions and changes in detail will readilyoccur IOU to those skilled in the art without departing from the spiritof my invention.

Therefore, having now set forth the objects and nature of my invention,and having shown and described an operative structure embodying theprinciples thereof, what I claim as new and of my own invention, anddesire to secure by Letters Patent is:

1. In an electric engine for operating a hinged car door, thecombination with an electric motor, a Worm associated with the armaturethereof, a worm wheel meshing with said worm and positively driventhereby, and a friction disk rigid with respect to said Worm wheel, of adoor shaft, a gear fixed thereon, a pinion meshing with said gear, afriction disk rigid with the pinion, and means for maintaining saidfriction disks in engagement under elastic pressure.

2. In an electric engine for operating a hinged car door, thecombination with an electric motor, a worm associated with the armaturethereof, a worm wheel meshing with said worm and positively driventhereby, and a friction disk rigid with respect to said worm wheel, of adoor shaft, a gear segment fixed thereon, a pinion meshing with saidgear segment, a friction disk rigid with the pinion, and means formaintaining said friction disks in engagement under elastic pressure.

3. In door operating apparatus of a car, the.

combination with an engine operatively connected to the door andincluding, as a prime mover, a reversible electric motor, of means forcontrolling the operations of said motor in either direction, and meansfor rendering the operations of the motor dependent upon the stopping ofthe associated car.

4. In operating apparatus for hinged and folding doors, the combinationwith a door operating engine comprising a reversible electric motoroperatively connected to an associated door through friction driveconnections, of current switching means for controlling the direction offeed of current to the motor to thereby control the direction ofoperation of the motor, and automatically operated switching means forrendering the motor inoperative except at predetermined times.

5. In door operating apparatus of a car, the combination with a door, ofa prime mover, operative connections, including friction drive meansbetween the prime mover operable means adapted when manually actuated torelease the door at any time.

7. In an electric engine for operating a car door, the combination witha casing provided with an opening through which a door shaft is adaptedto, project into the casing, a bearing associated with said opening andshaft to mount the shaft for rotation in the opening, a door operatingelement adapted to be secured to the shaft within the casing, anelectric motor positioned within the easing, bearingsv formed in thecasing for supporting the armature shaft of the motor for rotation, aworm fixed on the armature shaft, a stub shaft positioned within andrigid with the casing, a worm wheel mounted to rotate freely on the stubshaft while in mesh with the worm, a friction disk associated with saidworm wheel, a pinion meshing with the door operating element and mountedto freely rotate on the stub shaft, a friction disk rigid with thepinion, and means for maintaining said friction disks in engagementunder elastic pressure to afford a yieldable driving connection betweenthe motor and the door operating element.

In testimony whereof I have hereunto set my hand on this 18th day ofNovember, A. D. 1924.

HAROLD ROWN TREE.

